DO280 - ch02s02

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Guided Exercise: OpenShift Templates

Deploy and update an application from a template that is stored in another project.

Outcomes

Deploy and update an application from a template.

As the student user on the workstation machine, use the lab command to prepare your system for this exercise.

This command ensures that all resources are available for this exercise.

[student@workstation ~]$ lab start packaged-templates

Instructions

[student@workstation ~]$ oc login -u developer -p developer \
  https://api.ocp4.example.com:6443
Login successful.
...output omitted...

Examine the available templates in the cluster, in the openshift project. Identify an appropriate template to deploy a MySQL database.

Use the get command to retrieve a list of templates in the cluster, in the openshift project.

[student@workstation ~]$ oc get templates -n openshift
NAME                      DESCRIPTION            PARAMETERS        OBJECTS
...output omitted...
mysql-ephemeral           MySQL database...       8 (3 generated)  3
mysql-persistent          MySQL database...       9 (3 generated)  4
...output omitted...

Use the oc process --parameters command to view the parameters of the mysql-persistent template.

[student@workstation ~]$ oc process --parameters mysql-persistent \
  -n openshift
NAME                    DESCRIPTION   GENERATOR           VALUE
MEMORY_LIMIT            ...                               512Mi
NAMESPACE               ...                               openshift
DATABASE_SERVICE_NAME   ...                               mysql
MYSQL_USER              ...           expression          user[A-Z0-9]{3}
MYSQL_PASSWORD          ...           expression          [a-zA-Z0-9]{16}
MYSQL_ROOT_PASSWORD     ...           expression          [a-zA-Z0-9]{16}
MYSQL_DATABASE          ...                               sampledb
VOLUME_CAPACITY         ...                               1Gi
MYSQL_VERSION           ...                               8.0-el8

All the required parameters have either default values or generated values.

Use the mysql-persistent template to deploy a database by processing the template.

Create the packaged-templates project.

[student@workstation ~]$ oc new-project packaged-templates
Now using project "packaged-templates" on server ...
...output omitted...

Use the oc new-app command to deploy the application.

[student@workstation ~]$ oc new-app --template=mysql-persistent \
  -p MYSQL_USER=user1 \
  -p MYSQL_PASSWORD=mypasswd
--> Deploying template "packaged-templates/mysql-persistent" to project packaged-templates
...output omitted...
--> Success
    Application is not exposed. You can expose services to the outside world by executing one or more of the commands below:
     'oc expose service/mysql'
    Run 'oc status' to view your app.

Use the watch command to verify that the pods are running. Wait for the mysql-1-deploy pod to show a Completed status. Press Ctrl+C to exit the watch command.

[student@workstation ~]$ watch oc get pods
NAME             READY   STATUS      RESTARTS   AGE
mysql-1-5t8h8    1/1     Running     0          83s
mysql-1-deploy   0/1     Completed   0          84s

Connect to the database to verify that it is working.

[student@workstation ~]$ oc run query-db -it --rm \
  --image registry.ocp4.example.com:8443/rhel8/mysql-80 \
  --restart Never --command -- \
  /bin/bash -c \
    "mysql -uuser1 -pmypasswd --protocol tcp \
    -h mysql -P3306 sampledb -e 'SHOW DATABASES;'"
mysql: [Warning] Using a password on the command line interface can be insecure.
+--------------------+
| Database           |
+--------------------+
| information_schema |
| performance_schema |
| sampledb           |
+--------------------+
pod "query-db" deleted

The query-db pod uses the mysql command from the mysql-80 image to send the SHOW DATABASES; query. The --rm option deletes the pod after execution terminates.

Deploy the application from the custom template, in the ~/DO280/labs/packaged-templates/custom-template/roster-template.yaml file, to the project. The application initializes and uses the database that the mysql-persistent template deployed.

Upload the custom template to the project.

[student@workstation ~]$ oc create -f \
  ~/DO280/labs/packaged-templates/custom-template/roster-template.yaml
template.template.openshift.io/roster-template created

Use oc get templates to view the available templates in the packaged-templates project.

[student@workstation ~]$ oc get templates
NAME             DESCRIPTION                       PARAMETERS   OBJECTS
roster-template  Example application for DO280...  8 (2 blank)  4

Use the oc process --parameters command to view the parameter of the roster-template template.

[student@workstation ~]$ oc process --parameters roster-template
NAME                   DESCRIPTION  GENERATOR  VALUE
IMAGE                  ...                     registry.../do280-roster:v1
APPNAME                ...                     do280-roster
NAMESPACE              ...                     packaged-templates
DATABASE_SERVICE_NAME  ...                     mysql
MYSQL_USER             ...
MYSQL_PASSWORD         ...
MYSQL_DATABASE         ...                     sampledb
INIT_DB                ...                     False

Use the oc process command to generate the manifests for the roster-template application resources, and use the oc apply command to create the resources in the Kubernetes cluster.
You must use the same database credentials that you used in an earlier step to configure the database, so that the application can access the database.
```
[student@workstation ~]$ oc process roster-template \
  -p MYSQL_USER=user1 -p MYSQL_PASSWORD=mypasswd -p INIT_DB=true | oc apply -f -
...output omitted...
secret/mysql configured
deployment.apps/do280-roster created
service/do280-roster created
route.route.openshift.io/do280-roster created
```

Use the oc get pods command to confirm that the application is running.

[student@workstation ~]$ oc get pods
NAME                           READY   STATUS      RESTARTS   AGE
do280-roster-c7f596dd8-pqvlv   1/1     Running     0          60s
mysql-1-bl97v                  1/1     Running     0          33m
mysql-1-deploy                 0/1     Completed   0          33m

Use the oc get routes command to view the routes.

[student@workstation ~]$ oc get routes
NAME           HOST/PORT                                               ...
do280-roster   do280-roster-packaged-templates.apps.ocp4.example.com   ...

Open the application URL in the web browser. The header confirms the use of version 1 of the application.
http://do280-roster-packaged-templates.apps.ocp4.example.com
Enter your information in the form and save it to the database.

Deploy an updated version of the do280/roster application from the custom template in the roster-template template. Use version 2 of the application and do not overwrite the data in the database.

Create a text file named roster-parameters.env with the following content:
```
MYSQL_USER=user1
MYSQL_PASSWORD=mypasswd
IMAGE=registry.ocp4.example.com:8443/redhattraining/do280-roster:v2
```
The option of using a parameter file helps version control software to track changes.

Use the oc process command and the oc diff command to view the changes in the new manifests when compared to the live application.

[student@workstation ~]$ oc process roster-template \
  --param-file=roster-parameters.env | oc diff -f -
diff -u -N ...output omitted...
--- /tmp/LIVE-1948327112/apps.v1.Deployment.packaged-templates...
+++ /tmp/MERGED-2797490080/apps.v1.Deployment.packaged-templates...
...output omitted...
               key: database-service
               name: mysql
         - name: INIT_DB
-          value: "true"
-        image: registry.ocp4.example.com:8443/redhattraining/do280-roster:v1
+          value: "False" 
+        image: registry.ocp4.example.com:8443/redhattraining/do280-roster:v2 
         imagePullPolicy: IfNotPresent
         name: do280-roster-image
         ports:

	The `INIT_DB` environment variable determines whether the application initializes the database. The default `False` value is used when the parameter is omitted. In the first deployment, the `INIT_DB` variable was set to the `True` value, so the database was initialized. In this second deployment, the deployment does not have to initialize the database again.
	The `IMAGE` parameter changes the image that the template uses.

Use the oc process command to generate the manifests for the roster-template application objects, and use the oc apply command to create the application objects. With the changes from a previous step, you use the IMAGE variable to use a different image for the update and omit the INIT_DB variable.
```
[student@workstation ~]$ oc process roster-template \
  --param-file=roster-parameters.env | oc apply -f -
secret/mysql configured
deployment.apps/do280-roster configured
service/do280-roster unchanged
route.route.openshift.io/do280-roster unchanged
```

Use watch to verify that the pods are running. Wait for the mysql-1-deploy pod to show a Completed status. Press Ctrl+C to exit the watch command.

[student@workstation ~]$ watch oc get pods
NAME             READY   STATUS      RESTARTS   AGE
do280-roster-c7f596dd8-ktlvl   1/1     Running     0          60s
mysql-1-bl97v                  1/1     Running     0          53m
mysql-1-deploy                 0/1     Completed   0          53m

Open the application URL in the web browser. The route is unchanged, so you can refresh the previous browser page if the page is still open. The header confirms the use of version 2 of the application. The data that is pulled from the database is unchanged.
http://do280-roster-packaged-templates.apps.ocp4.example.com

Finish

On the workstation machine, use the lab command to complete this exercise. This step is important to ensure that resources from previous exercises do not impact upcoming exercises.

[student@workstation ~]$ lab finish packaged-templates

Discuss Red Hat OpenShift Administration II: Configuring a Production Cluster

Go to community

Red Hat OpenShift Administration II: Operating a Production Kubernetes Cluster (DO280)

Haley_Ruccio

26 lip 2023

Configure, manage, and troubleshoot OpenShift clusters and containerized applicationsRed Hat OpenShift Administration II: Operating a Production Kubernetes Cluster (DO280) prepares OpenShift Cluster Administrators to perform daily administration tasks on clusters that host applications provided by internal teams and external vendors, enable self-service for cluster users with different roles, and deploy applications that require special permissions such as such as CI/CD tooling, performance monitoring, and security scanners. This course focuses on configuring multi-tenancy and security features of OpenShift as well as managing OpenShift add-ons based on operators.The skills you learn in this course can be applied using all versions of OpenShift, including Red Hat OpenShift on AWS (ROSA), Azure Red Hat OpenShift, and OpenShift Container Platform.This course is based on OpenShift Container Platform 4.12.5-10 Course TopicsDeploying packaged applications using manifests, templates, kustomize, and helm.Configuring authentication and authorization for users and applications.Protecting network traffic with network policies and exposing applications with proper network access.Deploying and managing applications using resources manifests.Enabling developer self-service of application projects.Managing OpenShift cluster updates and Kubernetes operator updates.Target AudienceSystem Administrators and Platform Operators interested in the ongoing management of OpenShift clusters, applications, users, and add-ons.Site Reliability Engineers interested in the ongoing maintenance and troubleshooting of Kubernetes clusters.System and Software Architects interested in understanding the security of an OpenShift cluster.Recommended TrainingTake our free assessment to gauge whether this offering is the best fit for your skills.Prerequisite: Red Hat OpenShift I: Containers & Kubernetes (DO180 v4.12), or equivalent skills deploying and managing Kubernetes applications using the OpenShift web console and command-line interfaces.Technology considerationsThis course requires internet access to access the cloud-based classroom environment that provides an OpenShift cluster and a remote administrator’s workstation.

476

About pod security standards and warnings

alexcorcoles

17 kwi 2023

(This material has been created with the inputs of instructors and other people. We are trying to get this material published as soon as possible to address some concerns with DO180 and DO280.)With the default configuration, any namespace that you create on OpenShift 4.12 has the following labels: pod-security.kubernetes.io/audit: restrictedpod-security.kubernetes.io/audit-version: v1.24pod-security.kubernetes.io/warn: restrictedpod-security.kubernetes.io/warn-version: v1.24 These labels activate auditing and warning of the restricted pod security standard. The Kubernetes documentation describes the restricted pod security standard. Pod security standards such as restricted are not directly related to security context constraints such as the restricted SCC.Kubernetes uses an admission controller to reject pods that do not comply with pod security standards. An admission controller is a Kubernetes component that inspects every Kubernetes resource before its creation, and acts before Kubernetes creates the resource. This action can include rejecting the creation of the resource, or modifying the resource.The pod security standards are policies that include properties that workloads must follow. For example, the restricted standard requires that containers set the securityContext.allowPrivilegeEscalation field to false.Pod security standards apply both to workloads, such as deployments and jobs, and to pods.When a pod is created, the admission controller inspects the container specifications and enumerates the fields that violate the pod security standard of the namespace. The admission controller inspects the pod-security labels in the namespace to decide which pod security standard to apply (restricted, baseline, or privileged), and which action to take on violations. Namespaces can audit, warn, or enforce pod security standard violations. When the pod-security.kubernetes.io/audit annotation is set to restricted, the admission controller prevents the creation of pods that violate the security standard. When the pod-security.kubernetes.io/audit and pod-security.kubernetes.io/warn annotations are defined in the project, the admission controller does not block the creation of pods, but registers audit events or warnings.The admission controller does not enforce pod security standards for workloads. If the namespace is configured to enforce a pod security standard, then you can create a violating workload. The admission controller enforces only pod security policies on pods.Cluster administrators can use pod security standards to ensure that pods and workloads in namespaces limit their privileges. By limiting privileges, cluster administrators can mitigate what malicious pods can do.The default configuration of user namespaces in OpenShift does not restrict any workload; it only notifies users when they create workloads that do not follow pod security standards that might be enforced in future OpenShift versions.Security Context ConstraintsOpenShift introduced security context constraints (SCC) before the introduction of pod security standards in Kubernetes. SCCs automatically make security modifications to pods when they are created. By default, the system:openshift:scc:restricted-v2 cluster role binding applies to all authenticated users, so regular user workloads use the restricted-v2 SCC. For example, when you execute the following command to create a workload without any security configuration, the SCC adds security configuration to the pods: [user@host ~]$ oc create deployment test --image registry.ocp4.example.com:8443/redhattraining/hello-world-nginx (You can add the --dry-run=client -o yaml options to view the deployment manifest. The deployment manifest does not contain the security properties, which are described later.)If you inspect the pods that the deployment created, the SCC makes the following changes: [user@host ~]$ oc get pod test-b8d5658b6-7bxfs -o yamlapiVersion: v1kind: Podmetadata: annotations:... output omitted... openshift.io/scc: restricted-v2 seccomp.security.alpha.kubernetes.io/pod: runtime/default...output omitted...spec: containers: - image: registry.ocp4.example.com:8443/redhattraining/hello-world-nginx imagePullPolicy: Always name: hello-world-nginx resources: {} securityContext: allowPrivilegeEscalation: false capabilities: drop: - ALL runAsNonRoot: true runAsUser: 1000690000... output omitted... securityContext: fsGroup: 1000690000 seLinuxOptions: level: s0:c26,c20 seccompProfile: type: RuntimeDefault... output omitted... These restrictions satisfy the restricted pod security policy.The result of these defaults means that when creating a workload (such as a deployment) in a namespace without any customization, the restricted pod security standard applies, but the admission controller only warns and audits. If the workload does not satisfy the pod security standard, then the admission controller allows the workload to be created, but prints a message such as the following warning: Warning: would violate PodSecurity "restricted:v1.24": allowPrivilegeEscalation != false (container "example" must set securityContext.allowPrivilegeEscalation=false), unrestricted capabilities (container "example" must set securityContext.capabilities.drop=["ALL"]), runAsNonRoot != true (pod or container "database" must set securityContext.runAsNonRoot=true), seccompProfile (pod or container "example" must set securityContext.seccompProfile.type to "RuntimeDefault" or "Localhost") However, by default Kubernetes creates the deployment pods with the restricted-v2 SCC, with the restrictions that the previous warning included. Due to the following factors, workloads generate only a warning, and the pod security standard admission controller allows their pods:The pod security standard admission controller never enforces pod security standards on workloads (only on pods).By default, namespaces do not enforce pod security standards on pods.By default, regular workloads create pods by using the restricted-v2 SCC, which satisfies the restricted pod security standard.Even if future versions of OpenShift change the default namespace configuration to enforce the restricted pod security standard, users will continue to be able to create workloads without explicitly declaring the restrictions that the pod security standard requires, because the restricted-v2 SCC will apply such restrictions automatically.You can take the following approaches to handling pod security:For most workloads, the restricted-v2 SCC limits pod privileges adequately. When creating a workload, you receive the warning, but the workload creates pods and works correctly.You can also create your workloads by providing a full specification of the security constraints to apply, without relying on the SCC to provide the configuration. By following this approach, privileges are more explicit, and you have greater control, so you can adjust more precisely the specific privileges that are granted to workloads.When the restricted-v2 SCC and the default restricted pod security standard are not adequate for your workload, because either you require further privileges, or you need further restrictions, you must use an existing SCC, or create a custom SCC, and provide explicit security specifications. You can also adjust the namespace labels to choose a different pod security standard, and decide to audit, log, or enforce the standard.

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Welcome to the Red Hat OpenShift Administration II (DO280) group in the Red Hat Learning Community!

Deanna

17 kwi 2023

We are excited to launch a space dedicated to the Red Hat Training course Red Hat OpenShift Administration II: Operating a Production Kubernetes Cluster!To gain the most value from this group - click the "Join Group" button in the upper right hand corner.We encourage group members to collaborate in this group to discuss topics, ask questions, share best practices and tips, provide course feedback, and share their accomplishments as it relates to DO280.Read more about Red Hat OpenShift Administration II here.Thanks!

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Revision: do280-4.14-08d11e1